Drug retaining surface features in an implantable medical device

Abstract

An implantable component of a medical device, comprising a polymeric surface. The component includes one or more macro-surface features at the polymeric surface having a configuration that, following application of a liquid drug to the surface retains a quantity of the liquid drug adjacent the surface.

What is claimed is: 
     
       1. An elongate implantable stimulating assembly, comprising:
 a carrier member; 
 a plurality of electrode contacts disposed in a first portion of the carrier member; and 
 one or more macro-surface features, including at least one indentation or at least one protrusion, disposed in a second portion of the carrier member, 
 the macro-surface features having a configuration that enables the carrier member, following application of a liquid drug having cohesive forces to the carrier member, to retain a quantity of the drug. 
 
     
     
       2. The carrier member of  claim 1 , wherein the indentations comprise a roughened, undulating region of the carrier member having a having a plurality of ridges and valleys. 
     
     
       3. The carrier member of  claim 1 , wherein the indentations are apertures in the carrier member. 
     
     
       4. The carrier member of  claim 3 , wherein the apertures are lateral apertures extending from the lateral surface towards the center of the carrier member. 
     
     
       5. The carrier member of  claim 3 , wherein the apertures are transverse apertures extending transversely through a portion of the carrier member. 
     
     
       6. The carrier member of  claim 1 , wherein the macro-surface features are longitudinal channels in the carrier member. 
     
     
       7. The carrier member of  claim 1 , wherein the macro-surface features are transverse channels in the carrier member. 
     
     
       8. The carrier member of  claim 1 , wherein the protrusions are substantially planar protrusions having a curved outer surface. 
     
     
       9. The carrier member of  claim 1 , wherein the protrusions are bumps extending from the carrier member surface. 
     
     
       10. The carrier member of  claim 1 , wherein the protrusions are fibrous protrusions. 
     
     
       11. The carrier member of  claim 1 , wherein the carrier member is a first material, and wherein the protrusions are a second material. 
     
     
       12. The carrier member of  claim 11 , wherein the protrusions are a bio-resorbable material. 
     
     
       13. The carrier member of  claim 1 , wherein the one or more macro-surface features comprise an absorbent layer attached to the carrier member surface. 
     
     
       14. The carrier member of  claim 1 , further comprising:
 a first arrangement of macro-surface features at a first region of the carrier member; and 
 a second arrangement of macro-surface features at a second region of the carrier member. 
 
     
     
       15. The carrier member of  claim 1 , further comprising:
 a drug release impeding coating. 
 
     
     
       16. A method of delivering drugs to a recipient using an implantable component of a medical device, wherein the component comprises a plurality of electrode contacts disposed in a first portion of the implantable component and a plurality of macro-surface features, including at least one indentation or at least one protrusion, disposed in a second portion of the carrier member, the macro-surface features having a configuration that enables the implantable component to retain a quantity of a liquid drug, the method comprising:
 applying one or more liquid drugs to the component; and 
 implanting the implantable component into the recipient. 
 
     
     
       17. The method of  claim 16 , wherein applying the one or more liquid drugs to the carrier member comprises:
 dipping a first length of the carrier member into a first liquid drug; and 
 dipping a second length of the carrier member into a second liquid drug. 
 
     
     
       18. The method of  claim 17 , wherein the first length of the carrier is different than the second length of the carrier member. 
     
     
       19. The method of  claim 17 , wherein the first length of the carrier is the same as the second length of the carrier member. 
     
     
       20. The method of  claim 16 , wherein applying the one or more liquid drugs to the carrier member comprises:
 dipping a first length of the carrier member into a first liquid drug; and 
 dipping a first portion of the first of the carrier member into a removal solution so as to remove the first drug from the first portion; 
 dipping the first portion of the carrier member into a second liquid drug. 
 
     
     
       21. The method of  claim 16 , further comprising:
 coating the carrier member with a drug release impeding material. 
 
     
     
       22. An implantable component of a medical device, comprising:
 a polymeric surface; 
 a plurality of electrode contacts disposed in a first portion of the polymeric surface; and 
 one or more macro-surface features, including at least one indentation or at least one protrusion, disposed in a second portion of the polymeric surface, the marco-surface features having a configuration that enables the carrier member, following application of a liquid drug having cohesive forces to the surface, to retain a quantity of the liquid drug adjacent the surface. 
 
     
     
       23. The implantable component of  claim 22 , wherein the indentations comprise a roughened, undulating region of the component having a having a plurality of ridges and valleys. 
     
     
       24. The implantable component of  claim 22 , wherein indentations are apertures in the component. 
     
     
       25. The implantable component of  claim 24 , wherein the component is a stimulator/receiver unit. 
     
     
       26. The implantable component of  claim 22 , wherein the indentations are channels in the surface of the component. 
     
     
       27. The implantable component of  claim 22 , wherein the protrusions are fibrous protrusions. 
     
     
       28. The implantable component of  claim 22 , wherein the polymeric surface is a first material, and wherein the protrusions are a second material. 
     
     
       29. The implantable component of  claim 28 , wherein the protrusions are a bio-resorbable material. 
     
     
       30. The implantable component of  claim 22 , wherein the one or more macro-surface features comprise an absorbent layer attached to the polymeric surface. 
     
     
       31. The implantable component of  claim 22 , wherein the one or more surface features comprise:
 a first arrangement of macro-surface features at a first region of the component surface; and 
 a second arrangement of macro-surface features at a second region of the component surface. 
 
     
     
       32. An implantable component of a medical device, comprising:
 a polymeric surface; 
 a plurality of electrode contacts disposed in a first portion of the polymeric surface; and 
 one or more protrusions at the polymeric surface, disposed in a second portion of the carrier member, the macro-surface features having a configuration that enables the carrier member, following application of a liquid drug having cohesive forces to the surface, to retain a quantity of the liquid drug adjacent the surface. 
 
     
     
       33. The implantable component of  claim 32 , wherein the protrusions are fibrous protrusions. 
     
     
       34. The implantable component of  claim 32 , wherein the polymeric surface is a first material, and wherein the protrusions are a second material. 
     
     
       35. The implantable component of  claim 34 , wherein the protrusions are a bio-resorbable material. 
     
     
       36. The implantable component of  claim 34 , wherein the protrusions are substantially planar protrusions having a curved outer surface. 
     
     
       37. The implantable component of  claim 34 , wherein the protrusions are bumps extending from the surface of the component.